Related Experiment Video
Updated: Jul 19, 2025

Preparation of Free-Surface Hyperbolic Water Vortices
Published on: July 28, 2023
Preparation of Free-Surface Hyperbolic Water Vortices
Roman Klymenko1, Harmen Nanninga2, Esther de Kroon3
1Wetsus - Centre of Excellence for Sustainable Water Technology; Department of Electrical Engineering, Electrical Energy Systems group, Eindhoven University of Technology.
None:
Free surface vortices are present in industry in flow regulation, energy dissipation, and energy generation. Although investigated extensively, detailed experimental data regarding free surface vortices are lacking, particularly regarding the turbulence at the interface. The present paper reports on a special type of free surface vortex first proposed by Walter Schauberger in the 1960s that has an oxygen volumetric mass transfer coefficient exceeding the value of similar systems. This special type of vortex forms in a hyperbolic funnel. Different stable regimes can be stabilized with different hydraulic characteristics. Other advantages of this technology are its energy efficiency, simple design, and scalability. The flow in this hyperbolic funnel is characterized by strong turbulence and an increased surface area of the air-water interface. The local pressure strongly varies along the surface, resulting in a pronounced wavey air-water boundary layer. Due to the helical flow, these perturbations move inward, pulling the boundary layer with them. The resultant pressure gradient draws a certain air volume into the water vortex. The construction of the basic hyperbolic funnel setup and operational examples, including high-speed visualization for three different stable regimes, are presented in this work.
Related Concept Videos
Hydrostatic Pressure Force on a Curved Surface
Surface Tension of Fluid
Surface tension varies...
Hydrostatic Pressure Force on a Plane Surface
Buoyancy and Stability for Submerged and Floating Bodies
Newtonian Fluid: Problem Solving
A velocity gradient forms within the fluid when a Newtonian fluid is placed between two parallel plates, with...
Turbulent Flow: Problem Solving
Temperature is a key factor in CO2 solubility. In this case, the CO2 gas and the liquid are cooled to 20°C. Lower temperatures...

